Australian Tropical Rainforest Plants - Online edition

Pachygone ovata (Poir.) Miers ex Hook.f. & Thomson


Vine
Click/tap on images to enlarge
Female flowers. © CSIRO
Male flowers. © CSIRO
Leaves and fruits. © CSIRO
Leaves and male flowers. © CSIRO
Scale bar 10mm. © CSIRO
1st leaf stage, cotyledons absent. © CSIRO
10th leaf stage. © CSIRO
Vine stem bark and vine stem transverse section. © CSIRO
Family

Roxburgh, W. in Carey, W. (ed.) (1855) Flora Indica 1: 203.

Stem

Vine stem diameters to 10 cm recorded. Living bark layer very thin. Narrow concentric rings of included bark visible in transverse sections of the stem. 'Growth rings' visible in the bark.

Leaves

Leaf blades +/- papery, about 4-15 x 2-9 cm, petioles about 1.2-6.5 cm long, very thin, about 1 mm diam. Upper and lower leaf blade surfaces often clothed in pale hairs. Oak grain visible in the twigs.

Flowers

Male flowers: Inflorescence about 5-15 cm long, consisting of a number of short racemes on a central axis. Sepals three + three in two whorls, the outer ones smaller, about 1 mm long, inner sepals much wider and about 2 mm long. Petals about 1.5 mm long, the base bilobed, the lobes clasping or enveloping the base of the staminal filament. Stamens five or six per flower, filaments about 1-1.5 mm long. Female flowers: Inflorescence a raceme. Sepals three + three in two whorls, the outer ones smaller, about 1-1.5 x 1 mm, inner sepals about 2 x 2 mm. Petals six, about 1.5 x 1 mm, basal auricles enveloping the base of the staminodes. Staminodes small, usually six. Carpels three, placed close together, stigma sessile at the apex of each carpel and projecting +/- at right angles to the axis of the carpel.

Fruit

Fruits globose, slightly compressed laterally, about 6-7 mm diam. Style persistent, located close to the base of the fruit. Seeds (endocarps) about 5-6 x 5 mm, laterally compressed, outer surface somewhat sculptured. Embryo U-shaped. Cotyledons U-shaped, about 8-10 mm long. Radicle about 0.5-0.6 mm long. Endosperm scanty.

Seedlings

Cataphylls 1 or 2, produced before the first pair of true leaves. First pair of true leaves +/- cordate, apex acute, base cordate. Both the upper and lower surfaces of the leaf blades clothed in hairs. Margins usually with one large tooth or small lobe on each side. Pulvinus present on the petiole. At the tenth leaf stage: leaf blade cordate, about 9-10 x 5-6 cm, apex acuminate to apiculate, base cordate, midrib slightly raised on the upper surface. Terminal bud and stem clothed in brown hairs. Seed germination time 22 to 38 days.

Distribution and Ecology

Occurs in WA, NT, CYP, NEQ and CEQ. Altitudinal range from near sea level to 500 m. Grows in beach forest, monsoon forest and the drier more seasonal rain forests. Also occurs in Sri Lanka, SE Asia and Malesia.

Synonyms
Cissampelos ovata Poir., Encycl. Meth. Bot. 5: 10(1804), Type: Indes orientales, P. Sonnerat. Holo: P?. Pachygone ovata var. dasyphylla Miq., Annales Musei Botanici Lugduno-Batavi 4 : 87(1868), Type: Iava: HORSFIELD. Pachygone pubescens Benth., Flora Australiensis 1: 58(1863), Type: Queensland. Quail Island, Sept 1855, J. Flood. Holo: K. Iso: MEL. Cebatha pubescens (Benth.) Kuntze, Revisio Generum Plantarum 1: 9(1891). Tristichocalyx pubescens (Benth.) F.Muell., Fragmenta Phytographiae Australiae 4: 27(1863). Tinospora hullsii F.Muell., Fragmenta Phytographiae Australiae 5: 147(1866), Type: Northern Territory, Escape Cliffs, C. Hulls. Holo: MEL. Iso: BRI, K. Pachygone hullsii (F.Muell.) F.Muell., Fragmenta Phytographiae Australiae 9: 81(1875).
RFK Code
2136
Copyright © CSIRO 2020, all rights reserved.